We've had a couple of fights with other clans the pas weeks..
You should check the settings you're playing with, just a suggestion!

To be playing stopwatch with XPSave isn't fair play for either side. For instance, say that team one plays well as attackers on goldrush, thus generating good XP and also a very low time, what happens when its the other teams turn?

Well, the other team has to attack in a faster time, although with a lower XP ratio and therefore lower stats on class skill etc.

For a SW game to be fair XP reset should occur with every map and every teamswitch, don't you agree?

I strongly suggest that you think about using other settings than the ones you use on the public server. We went over to using ETPro with a predefined certified (the game itself reports that the settings are certified) configuration file (for instance clanbase or rtcw.no config)